why wont my ubuntu 10.04 upgrade to 10.10

[Vokam]

I am trying to upgrade my Ubuntu to 10.10. i've ran all the updates and when i get to press upgrade to 10.10 in the update manager, It gets a few files then first this message;

Third party sources disabled
Some third party entries in your sources.list were disabled. You can re-enable them after the upgrade with the 'software-properties' tool or your package manager.

On closing the window, it seems to continue installing, then this:

Could not determine the upgrade

An unresolvable problem occurred while calculating the upgrade:
E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.

[COLOR="blue"]This can be caused by:
* Upgrading to a pre-release version of Ubuntu
* Running the current pre-release version of Ubuntu
* Unofficial software packages not provided by Ubuntu

If none of this applies, then please report this bug against the 'update-manager' package and include the files in /var/log/dist-upgrade/ in the bug report.


Please help me out someone.
Thanks in advance.

[kansasnoob]

Look at what I've suggested here:

http://ubuntuforums.org/showthread.php?t=1682856

It's doubtful that you'll have the identical repo installed but maybe you'll understand the idea.

[Vokam]

Look at what I've suggested here:

http://ubuntuforums.org/showthread.php?t=1682856

It's doubtful that you'll have the identical repo installed but maybe you'll understand the idea.
Thanks mate, I tried your suggestion, seems to have worked. Installed and even rebooted properly, but now the ubuntu 10.10 it won't start since the last time I shut it down. Am at my wits end. Any suggestions would be appreciated.Thanks